The Fukushima No. 1 Nuclear Power Plant is seen in this file photo taken from a Mainichi Shimbun helicopter on July 17, 2018.

The Nuclear Regulation Authority (NRA) plans to require that highly radioactive waste generated when nuclear reactors are decommissioned be buried underground at least 70 meters deep for about 100,000 years until the waste becomes no longer hazardous.

Moreover, disposal sites for such waste should not be built in areas that could be affected by active faults or volcanoes.

The plan is part of the proposed regulatory standards on disposal sites for radioactive waste from dismantled nuclear reactors, which the NRA approved on Aug. 1. The NRA will hear opinions from power companies operating nuclear plants and other entities before finalizing the regulatory standards.

Low-level radioactive waste generated when reactors are dismantled is graded by three ranks in descending order from L1 to L3.

The proposed regulatory standards cover L1 waste, such as containers for control rods and fuel assemblies.

There have been no regulatory standards for L1 radioactive waste even though a growing number of nuclear reactors are bound to be decommissioned under the regulatory standards for nuclear plants that have been stiffened following the outbreak of the Fukushima nuclear crisis in March 2011.

Under the proposed regulatory standards for L1 waste, electric power companies would be required to build disposal sites on stable ground. Such facilities should not be built near faults at least 5 kilometers in length. Moreover, utilities would be mandated to confirm from records or geological surveys that there has been no volcanic activity over the past 2.6 million years or so near where they plan to build the disposal sites.

Power companies would also be obligated to avoid building disposal sites near oil or mineral deposits because areas with such natural resources may be excavated in the future.

Such radioactive waste must be regularly monitored over a roughly 300- to 400-year period following its disposal to see if the waste contaminates nearby groundwater. The owners of disposal sites would then be banned from digging areas surrounding the facilities without permission from the central government.

The proposed standards also require that additional radiation exposure dosages from disposal sites be limited to 0.3 millisieverts or less a year in accordance with international standards. It is also required to confirm whether radiation doses would be below that limit even if the functions for shielding radiation were partially lost, such as the container holding radioactive waste being broken, by analyzing doses under such scenarios.

1.This Month

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Changing climate change“2040” paints an optimistic picture of the future of the environment

The film focuses on technological and agricultural solutions that are already being implemented to help combat climate change, The Economist Feb 19th 2019

by C.G. | BERLIN ……….In “2040”, a documentary which premiered at the Berlinale, Mr Gameau seeks to wrest hope from the bleak reports of climate change. He was inspired by Project Drawdown, the first comprehensive plan to reverse global warming, and the film is intended as a “virtual letter to his four-year-old daughter to show her an alternative future”. “Many films,” Mr Gameau thinks, are too dystopian, and “paint a future that is really hard to engage and to connect with”. “2040” acknowledges that the Earth has set off down a hazardous path, but focuses on the work that is being done now to steer the right course. What, the film asks, could make 2040 a time worth living in?…. (subscribers only) https://www.economist.com/prospero/2019/02/19/2040-paints-an-optimistic-picture-of-the-future-of-the-environment